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Cerebellum is a profound structure of the central nervous system. Human cerebellum weighs about 150 g which represents around 10% of the total weight of the brain. It receives main input from sensory systems but the cerebellum functions as a part of the motor system. The cerebellum contributes by only few direct connections to motoneurons (therefore it cannot initiate any motor activity) but it projects profusely to all major motor control regions of the cerebral cortex. The cerebellum acts as a controller and coordinator. It compares movement intention with, performance and coordinates the equilibrium, posture and muscle tone necessary for the smooth coordinated motor activity. The number of input projections which exceed considerably the output ones (40:1) speaks out of an enormous analytical and synthetic capacity of the cerebellum. Interneuronal transmission of informations and carriage of afferent and efferent signals are provided by wide variety of chemical messengers (amino acids, biogenic amines and neuropeptides) of the local origin or delivered from the precerebellar nuclei. Direct and reciprocal connections between the hypothalamus and cerebellum have anatomically been well documented but monosynaptic contacts between the cerebellum and the hypothalamic paraventricular nucleus have not been approved yet. Cerebellum can respond to stress, however, this response may not be related only to the primary effect of the stressor but also to its consequences.